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SYS_DMA_ChannelIsBusy Function</div>
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This function returns the busy status of the DMA channel. DMA channel will be busy if any transfer is in progress.&nbsp;</p>
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This function can be used to check the status of the channel prior to submitting a transfer request. And this can also be used to check the status of the submitted request if callback mechanism is not preferred.</p></div>
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C</div>
<div class="Element101"><div class="Element100"><pre class="Element100"><strong><span style="color: #000080">bool</span></strong> <strong><span style="color: #000000">SYS_DMA_ChannelIsBusy</span></strong>(
    <a href="00864.html" target="topic">SYS_DMA_CHANNEL</a> <strong><span style="color: #000000">channel</span></strong>
);</pre></div></div>
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Preconditions</div>
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DMA Controller should have been initialized.</p></div>
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Parameters</div>
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Parameters&nbsp;</div></td><td class="Element304" valign="top" width="65%">
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Description&nbsp;</div></td></tr><tr>
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channel&nbsp;</div></td><td class="Element306" valign="top" width="65%">
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A specific DMA channel&nbsp;</div></td></tr></table></div></div>
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Returns</div>
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Busy status of the specific channel.</p>
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<li class="Element600">True - Channel is busy</li>
<li class="Element600">False - Channel is free</li>
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Remarks</div>
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None.</p></div>
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Example</div>
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<div class="Element13"><div class="Element12"><pre class="Element12"><i><span style="color: #008000">// Transfer 10 bytes of data to UART TX using DMA channel 1</span></i>
<i><span style="color: #008000">// DMA Channel has been configured and initialized by appropriate PLIB call.</span></i>

uint8_t buf[10] = {0,1,2,3,4,5,6,7,8,9};
<strong><span style="color: #000080">void</span></strong> *srcAddr = (uint8_t *) buf;
<strong><span style="color: #000080">void</span></strong> *destAddr = (uin8_t*) &amp;U1TXREG;
size_t size = 10;

<strong><span style="color: #000080">if</span></strong>(<strong><span style="color: #000080">false</span></strong> == SYS_DMA_ChannelIsBusy(SYS_DMA_CHANNEL_1))
{
    <a href="00872.html" target="topic">SYS_DMA_ChannelTransfer</a>(SYS_DMA_CHANNEL_1, srcAddr, destAddr, size);
}</pre></div></div>
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